查询词典 dopa

The synthesis of the pentacyclic skeleton of Et-743 and the construction of the five chiral centers thereof.1. The core pentacyclic skeleton of phthalascidin was constructed with L-dopa as the starting material via thirteen steps. First, two basic synthons, the C-1 functionalized tetrahydroisoquinoline compounds 8 and N-protected Z-dopa derivative 9, were prepared from L-dopa. They were coupled via amide bond to form the dipeptide compounds 10, which were the first key intermediates. Then the primary hydroxyl groups were transformed into the corresponding amino aldehydes 11 via Swern oxidation. Followed by the intramolecular Pictet-Spengler cyclization, the pentacyclic compounds 12 were synthesized.

五环骨架的构建及五个正确手性中心的确立：1.1我们以L-多巴为起始原料，经过多步官能团保护和转化合成了基本结构单元8然后和苯丙氨酸衍生物9，通过缩合反应生成酰胺中间体10，经Swern氧化得到醛化合物11，然后再次利用分子内改良的Pictet-Spengler反应一步构建c，d两环，得到五环骨架化合物12，最后，实现了21-位羰基向氰基的转化，得到了C-1位官能化的化合物14，化合物14不但具有和Et-743一致的五环骨架，而且分子中五个手性中心立体构型也与其完全相同：其中，3，位和13，位的手性中心由原料L-多巴带入，而1，位，11，位和21，位手性中心则通过不对称诱导而确立。

Vitamin C can interrupt the process of melanin production could have been generated to prevent further oxidation of DOPA ammonia was reduced to dopa, and can reduce serum levels of copper oxide, affecting the activity of tyrosine plum, thereby interfering with the biosynthesis of melanin, if the want to make the skin and fair complexion, we might eat more foods rich in vitamin C such as tomatoes, oranges, lemons, hawthorn, citrus and so on.

维生素C能中断黑色素生成的过程本来是可以防止的多巴氨进一步氧化减少到多巴，并能降低血清铜氧化，影响酪氨酸梅的活性，从而与黑色素的生物合成，如果干扰是想使皮肤白皙，我们可能会吃更多的食物含有丰富的维生素C，如西红柿，橙子，柠檬，山楂，柑桔等。

Receptor binding was found to be increased by 26%(p.05) in 6-OHDA lesioned side vs contralateral side in control rats. After 42-day administration of 1-dopa,〓 was reduced by 20%(p.05) in lesioned side. There was almost no difference of 〓 between 〓-dopa+〓-SPD-treated and vehicle-treated rats.

6—OHDA毁损的大鼠，给药42天后〓受体结合分析，对照组大鼠毁损侧〓受体增生，Bmax增加26%（P.05）；应用1—dopa组〓受体Bmax减少20%（P.05）；而1—dopa+1—SPD组〓受体与对照组相比无明显变化。

Auto-immune type: also known as methyl-dopa-type, hemolytic disease can be medication from 3 months to 4 years later, on behalf of drug: a - methyl-dopa, levodopa, phenytoin, phenacetin, chlorpromazine, indomethacin, etc.

自身免疫型：又称甲基多巴型，溶血发病可在服药3个月至4年后，代表药物有：a--甲基多巴、左旋多巴、苯妥英钠、非那西丁、氯丙嗪、吲哚美辛等

With L-DOPA as the starting chiral phenylalanine derivatives, construction of the skeleton of Phthalascidin was studied. Firstly, starting from L-DOPA and 3,4-dimethoxyphenylalanine, an amide 〓 was obtained, and a modeling cyclization reaction was carried out but failed to give the anticipated product.

二、对由苯丙氨酸甲酯衍生物通过Bischler-Napieralski反应合成四氢异喹啉—3—甲酯进行了研究，通过研究首次发现，生成苄基噁唑的反应是正常的B-N反应的竞争性反应，并从机理上给予了解释，所得出的结论具有一定的规律性，在杂环的合成方面具有一定的应用价值。

At the depigmentation assay, DH and EH show dose-dependently inhibitory activities against mushroom tyrosinase, and the IC50 is 5.697 and 5.256 mM, respectively, and show noncompetitively inhibitory modes in the present of tyrosine, but not DOPA. The control synthetic products, D and E, have no inhibitory effects on tyrosinase. Using tyrosinase activity staining in PAGE gels, both DH and EH show dose-dependently inhibitory pattern in the presence of tyrosine, while, EH also could suppress tyrosinase activity in the presence of DOPA.

而美白活性方面，以商品酪胺酸以商品酪胺酸酵素进行实验，当基质为酪胺酸时，发现DH与EH具浓度相关抑制效果，IC50分别为5.697与5.256 mM，且其相对於基质酪胺酸之抑制型态皆为非竞争型抑制，而其结构类似物之对照化合物D与E则不具此活性；但当基质为多巴时则皆不具此活性；利用原态PAGE电泳活性染色亦发现抑制酪胺酸酵素结果，但EH在基质为多巴时也能下降酪胺酸酵素活性。

TPS produces and sells pharmaceutical intermediates made from local resources, including L-dopa,Artemisinin ,artesunate, dihydro artemisinin, shikimic acid, mangiferin, camptothecin, star anise oil,ursolic acid , rosmarinic acid, anethole,etc.

产品有：左旋多巴，青蒿素，青蒿琥酯，双氢青蒿素，蒿甲醚，莽草酸，八角茴香油，芒果甙，喜树碱，熊果酸等当地资源生产加工的天然植物提取物。

The company mainly produces and sales of Products are: L-dopa, artemisinin, artesunate, dihydroartemisinin, shikimic acid, Star Anise Oil, Mangiferin, camptothecin, rosmarinic acid and other local resource production and processing of natural plant extracts.

公司主要生产及销售的产品有：左旋多巴、青蒿素、青蒿琥酯、双氢青蒿素、莽草酸、八角茴香油、芒果甙、喜树碱、迷迭香酸等当地资源生产加工的天然植物提取物。

Our company mainly production and sale of products are: L-dopa, artemisinin, artesunate, dihydroartemisinin, shikimic acid, mangiferin, Solanesol, camptothecin, Star Anise Oil, fans Diego Shannon acid and rosemary essential oils and other local resources for production and processing of pharmaceutical intermediates.

我们公司主要生产及销售的产品有：左旋多巴、青蒿素、青蒿琥酯、双氢青蒿素、莽草酸、芒果甙、茄尼醇、喜树碱、八角茴香油、迷迭香酸和迷迭香精油等当地资源生产加工的医药中间体。

The experiment indicated that the correlation coefficient between L-DOPA method and catechol method was 0.984, and reached the extremely significant level.

验证试验表明，邻苯二酚法和L-DOPA法的相关系数为0.984，且达极显著水平。

For the head-teacher of the class said that I had seriously broken the school rules,which led me to a three-day suspend class.

为什么呢？因为我的班主任说我严重的违反了校规，于是让我停课三天。

Many of them believe that the conversion of thousands of working-class folk in England spared that nation from the mass carnage and the tyranny that came with the revolution in France.

他们之中有许多人相信，在英国数以千计的劳工阶级之悔改信主使英国免於遭受如法国大革命所造成的大屠杀和专制暴政。